So what is Diabetes?
This is the first question I ask people before I actually get into the nitty gritty details of the subject. Approximately 95% of people (including those who have diabetes) don’t fully understand what diabetes is. The most common answer is “it is an increase in blood glucose (sugar)”, which is true of course, but when I follow on by saying “what is the reason for this increase in blood sugar?”, I hear the crickets ringing as most people can’t answer this question. So today I’m here to tell you all about diabetes and the reasoning behind why your GP or specialist is hounding on you to exercise for diabetes management.
Before I answer the question above I want to touch over four key items which play an important role before and after a diagnosis of diabetes:
Pancreas: This is a large gland which sits behind the stomach. Its main role is to secrete enzymes and hormones into the blood steam to assist with digestion.
Insulin: Insulin is a hormone secreted by the pancreas in an attempt to regulate blood sugar levels and to prevent a hypoglycaemic (low blood sugar) or hyperglycaemic (high blood sugar) event from occurring.
Glucose: This is a carbohydrate which is obtained from our food sources. Glucose is the simplest form of a carbohydrate (single sugar molecule after it has been broken down) and is the easiest form to store as fuel for our cells. Often glucose is referred to as sugar, eg. Blood sugar levels.
GLUT 4 Protein: Glucose Transporter Type 4, or GLUT 4, is a protein responsible for transporting glucose as fuel into adipose tissue (fat cells) and muscle cells around the body, and is regulated by insulin.
How does eating food increase my blood sugar levels and my chances of developing diabetes?
When we consume different foods and drinks, they are broken down into carbohydrates, protein and fat. Once broken down they are infused into the blood stream and transported around our body via our blood stream. I like to think of our blood stream as our own mini freeway, as it allows important items to travel from A to B. In terms of carbohydrates, when we consume foods and drinks high in sugar, we consequently are infusing higher levels of glucose into our blood stream. This would be like peak hour traffic on the M1 freeway, there’s a lot of cars and not much room to move. When this occurs, our Pancreas is alerted and produces increased amounts of insulin in order to quickly store glucose as fuel or fat in our cells. Hence, insulin regulates our blood sugar and we are no longer experiencing peak hour traffic conditions.
In the short term this is fine as your Pancreas is able to keep up with the work load, but is unable to sustain efficient production over a long period of time. It begins to produce poor quality insulin and eventually quits as it is working over-time without getting paid any extra money. This leads to constant elevated levels of sugar in the blood stream, which causes major consequences around the body. Imagine having to sit in constant peak hour traffic on the freeway 24 hours of the day! Well this is essentially what is happening in your body. This increase in blood sugar levels dramatically increases the volume and density of our blood and increases the difficulty for important items to be transported around the body in a timely fashion. So what does your body do to lessen the traffic jam? It opens a new lane on the freeway by drawing fluid from cells and diluting the blood sugar. Unfortunately, this does not help. Our cells need to keep hydrated to function efficiently; hence we consume more fluid to hydrate our now dehydrated cells. Thus, you spend more time on the toilet releasing our bowels and trying to get rid of the excess sugars, rather than exercising or spending time with our family.
Yet, if we come back to the reason in the first place as to why you are consuming more water, it is because you have too much glucose in your blood stream. So even though you have diluted the blood, there is still too much glucose in the blood stream and not enough insulin to transport glucose into our cells. Ultimately, you have created even more work for other organs in your body to try and regulate your blood sugar levels (which consequently can result in them burning out too).
This constant high level of blood glucose damages our Pancreas to the point that it either produces poor quality insulin (insulin resistance) or decides it’s time for retirement and quits, ultimately leading to constant high levels of blood glucose and the diagnosis of diabetes.
Other complicates that arise from this increase in blood glucose levels include, but are not limited to:
Damage to blood vessels (especially small vessels in your eyes)
Increased prevalence of skin infections and increase recovery/repair time
Bone and joint issues
Nerve damage (especially in your feet)
So we now understand what diabetes is, but why is exercise so important when you have diabetes?
In order for glucose to be stored in muscles as fuel, it needs to pass through a glucose channel (GLUT 4) at the membrane to the muscle, but without an insulin molecule, this cannot happen. Hence, insulin acts as a key to the door (GLUT 4) which allows glucose to pass through into the house (muscle). When we have poor quality of insulin, our insulin acts as ‘rusty keys’ which do not unlock the door to allow glucose to pass through. There are many medications which improve the sensitivity to insulin which allow glucose to enter through the doorway, however they do not improve the production of quality insulin. Now, I’m about to let you in on a little known secret about exercise. I’m sure most of you have heard of the saying “exercise is medicine, and medicine is exercise” or something quite similar to that. Well I’m here to tell you that exercise provides an extra benefit to diabetes that no medication is able to do. Exercise causes a series of multiple muscular contractions around the body and in order to keep up with the high demand for the muscle to work at a higher intensity, it needs to uptake fuel quicker than what you would need if you were sitting down at your work desk. But how does it do this if you have too many rusty keys which don’t open the doors to the muscle? By utilising a secret trap door. Muscular contraction allows for extra doorways which stay open and allow for a flooding of glucose fuel to enter through the doorway.
If you compare a small car with a 4-cylinder engine to a V8 turbo charged car, which car do you think would chew through its fuel quicker? The V8 would of course at it has a bigger engine so it needs to consume fuel quicker. The same principle works for our muscles, if you have large muscles or exercise at a higher intensity, you need to utilise more glucose to fuel your engine (aka your muscles). Ultimately this lowers and helps to regulate your blood glucose levels.
It’s important to note at this point in time that low levels of glucose in the blood can also be detrimental to how your body functions. Glucose is the sole source of fuel for your brain, so when levels are low it begins to steal glucose from other cells around the body. This can cause symptoms such as feeling lethargic, thirsty, blurry vision, low mood levels, weak and faint. This is known as a hypoglycaemic event and should be treated by consuming fast release glucose foods or drinks such as jelly beans or fruit juices, and your blood glucose levels should be checked straight away, then 5 minutes after consumption to see if levels are rising. If they are not then you should seek medical assistance.
Obviously exercise has other physical and health benefits such as reducing waist circumference, improving joint pain and health, improving cardiovascular health and improving your mental state. Yet there is one other benefit which many people do not know. It has been shown through research that regular exercise can have such a positive affect on your blood glucose levels that you may no longer need to take medication. “Exercise is Medicine, and Medicine is Exericse”. However there is insufficient evidence to support this with those who take insulin injections to regulate their blood glucose levels.
There are two types of diabetes. Type 1 occurs in 10-15% of diabetic people, has a genetic or autoimmune system dysfunction link and unfortunately has no cure. Type 2 is more prevalent and occurs in 85-90% of those with diabetes. Although it also has a link to genetics and ethnicity, you are at a higher risk of developing it if you are overweight, smoke, have high blood and/or cholesterol and make poor lifestyle choices in terms of food consumption and physical activity.
Even though Type 1 diabetes cannot be prevented, Type 2 diabetes can by improving your lifestyle choices and behaviours. 210 minutes of moderate intensity physical activity is recommended per week for health benefits (which if you do the maths is only 30 minutes per day), which can be broken up into smaller time intervals (eg. 3 x 10 minutes). This can help to regulate your blood glucose levels and ultimately reduce the likely-hood of developing further complications in the future.